bool Push( Stack S, ElementType X ){
	if(S->Top==S->MaxSize){
		printf("Stack Full\n");
		return false;
	}
		S->Top++;
		S->Data[S->Top]=X;
		return true; 
} 
ElementType Pop( Stack S ){
	int a; 
	if(S->Top==0){
		printf("Stack Empty\n");
		return ERROR;
	}
	a=S->Data[S->Top];
	S->Top--;
	return a;
}
